1. Field of the Invention
The present invention relates to a hand-held device and geographical positioning methods thereof, and more particularly to a hand-held device and its geographical positioning methods that reduce positioning data used for computing through the positioning methods and display geographical area data on a digital picture.
2. Description of the Prior Art
In a conventional technique, when a user uses a hand-held device having photographing and positioning functions, such as a digital camera, a cell phone or a navigator, he or she will activate a positioning module of the hand-held device to perform photographing. This hand-held device will access positioning data for a current geographical location through a global positioning system (GPS) and record data in an exchangeable image file format (EXIF) of a digital picture or directly display on the digital picture.
After accessing the positioning data, the navigator will perform geographical positioning to obtain a current location of the navigator itself. Yet the navigator obtains accurate geographical area data by scanning geographical area databases one by one and comparing positioning data with coordinates of each area.
From the aforementioned descriptions, the positioning data accessed by the navigator is normally numerical values of latitude-longitude coordinates. The user needs to input the latitude-longitude coordinates into the hand-held device or other electronic map system, which uses the latitude-longitude coordinates to search for a target location, so that a shooting place where the digital picture is taken can be known. Although the exchangeable image file of the digital picture can be used to store more diversified data, a program or machine capable of reading the exchangeable image file must be used to acquire the related data such as the shooting place where the digital picture is taken. Besides, since the hand-held device scans databases one by one and compares the positioning data with the coordinates of each area, the required hardware capability is also higher due to greater computation load of data.
As a result, how to quickly access data of the shooting place where the digital picture is taken to provide the user with a reference and how to quickly access the positioning data and the correspondingly geographical area data without increasing hardware design and manufacturing cost are an important issue.